Any discussion of the background art throughout the specification should in no way be considered as an admission that such art is widely known or forms part of common general knowledge in the field.
In artistic or developed multi-media content, the audio component is rarely just a capture or accurate representation of the sound that was or would have been present at the camera or video point of view. Generally, in creating media, various forms of post-processing are performed on the captured audio signals to enhance and/or modify them.
For conventional audio associated with multimedia productions, there are two main accepted approaches for creating a final produced audio mix. Generally, the audio is created and output in a predetermined format, which most often includes a set of audio channels for a specific speaker layout, or a set of channels with an additional coding structure that allows a decoder to subsequently decode the channels for a specific speaker layout. These two approaches are shown schematically in FIGS. 1 and 2.
The approach illustrated in FIG. 1 involves the use of captured and stored audio elements (stems) and a manual mixing and mastering process to create a theatrical or produced mix. The approach illustrated in FIG. 2 involves the use of an array of microphones or a spatial microphone with some optional format conversion or mapping to create a realistic impression of the original sound field in the final multichannel output.
There is a desire for the development of a more flexible format and representation of multichannel or spatial audio which allows for more flexibility and possibility at the point of output or rendering.